1. Field:
This invention relates to devices for supplying breathable gas to a patient. More particularly, this invention relates to disposable breathing systems and components thereof. Even more particularly, this invention relates in part to medical respiration or ventilation systems and anesthesia systems.
2. State of the Art:
Systems to ventilate a patient including anesthesia systems are in wide use today in the medical community. For example, a patient may be anesthetized such that mechanical means must be used to take over and ensure that the patient breaths. This enforced breathing or ventilation is today effected by interconnecting an anesthesia machine, a ventilation machine, and/or a breathing circuit to a patient, and more particularly to the external end of a endotracheal tube or mask which has been positioned in the patient's trachea.
In operation, the anesthesia machine supplies a mixture of breathable gas which typically includes an anesthetic mixed with air or oxygen. The ventilation machine operates to cause the anesthetic gas mixture and recycled respiratory gas to be supplied to the patient at a sufficient pressure to cause the gas mixture to pass through the breathing circuit and the endotracheal tube into the lungs of the patient. After inflating the lungs, the natural pressure of the expanded chest cavity will cause an expiration or a transfer of gas out of the patient back into the breathing circuit for reprocessing or recycling, all on a periodic basis which is typically set to accommodate the individual patient's breathing rate or respiration rate.
Ventilation systems that are in use typically include a ventilation device and/or a breathing circuit for interconnection to the patient in order to assist or to take over the breathing function for the patient. Such systems may be used during transport of the patient between two points for medical treatment or in an emergency situation where a patient has stopped breathing for whatever reason, and in other circumstances where the patient requires assistance in breathing for a limited or even an extended period of time based on a medical condition. The Ohio 7000 is one such ventilator machine. It is presently sold by Ohio Medical Products with offices at 3030 Airco Drive, Madison, Wis. 53707. The Ohio 7000 anesthesia ventilator may be used to control ventilation of a patient in a variety of circumstances including anesthesia. Breathing circuits, and more particularly disposable anesthesia circuits, may be purchased for interconnection with anesthesia machines and ventilation machines. A disposable breathing circuit may be purchased from Marquest Medical Products, Inc., of Englewood, Colo. 80112.
Anesthesia systems and ventilation systems are well known in the art. For example, U.S. Pat. No. 3,841,327 (Hay) discloses an anesthesia ventilator apparatus similar to that presently being sold as the Ohio 7000 ventilator apparatus. U.S. Pat. No. 3,903,881 (Wiegl) discloses a respirator system for use in ventilating a patient. U.S. Pat. No. 3,844,280 (Smythe); U.S. Pat. No. 3,921,628 (Smythe et al.); U.S. Pat. No. 3,916,890 (Freeman); and U.S. Pat. No. 3,467,092 (Bird et al.) all disclose ventilation and anesthesia apparatus or systems for use in ventilating the patient.
Many ventilation systems today employ a variety of components including a reservoir or respiration bag which is used continuously or from one patient to the next. That is, many of the components of a ventilation system are not disposable or simply not disposed of.
It is recognized within the medical community that some number of different diseases may be communicated from person to person through the oral transmission of organisms. Today there is increasing attention to AIDS prevention or control. The substantial unknowns associated with AIDS has precipitated increasing concern that infectious AIDS organisms may be communicated from one patient having the disease to the next by successive use of similar ventilation or anesthesia systems because the systems are not disposable and have not been thoroughly cleaned even though substantial effort may have been devoted to cleaning the systems.
In effect, an anesthesia system and a ventilation or transportation ventilation system is needed in which the breathing circuits can be disposable, while expensive anesthesia machines and ventilation machines are themselves isolated from the breathing circuit and the patient.